drivers/net/ethernet/amd/xgbe/xgbe-desc.c

   1 /*
   2  * AMD 10Gb Ethernet driver
   3  *
   4  * This file is available to you under your choice of the following two
   5  * licenses:
   6  *
   7  * License 1: GPLv2
   8  *
   9  * Copyright (c) 2014 Advanced Micro Devices, Inc.
  10  *
  11  * This file is free software; you may copy, redistribute and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 2 of the License, or (at
  14  * your option) any later version.
  15  *
  16  * This file is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19  * General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  *
  24  * This file incorporates work covered by the following copyright and
  25  * permission notice:
  26  *     The Synopsys DWC ETHER XGMAC Software Driver and documentation
  27  *     (hereinafter "Software") is an unsupported proprietary work of Synopsys,
  28  *     Inc. unless otherwise expressly agreed to in writing between Synopsys
  29  *     and you.
  30  *
  31  *     The Software IS NOT an item of Licensed Software or Licensed Product
  32  *     under any End User Software License Agreement or Agreement for Licensed
  33  *     Product with Synopsys or any supplement thereto.  Permission is hereby
  34  *     granted, free of charge, to any person obtaining a copy of this software
  35  *     annotated with this license and the Software, to deal in the Software
  36  *     without restriction, including without limitation the rights to use,
  37  *     copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  38  *     of the Software, and to permit persons to whom the Software is furnished
  39  *     to do so, subject to the following conditions:
  40  *
  41  *     The above copyright notice and this permission notice shall be included
  42  *     in all copies or substantial portions of the Software.
  43  *
  44  *     THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
  45  *     BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  46  *     TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  47  *     PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
  48  *     BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  49  *     CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  50  *     SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  51  *     INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  52  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  53  *     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  54  *     THE POSSIBILITY OF SUCH DAMAGE.
  55  *
  56  *
  57  * License 2: Modified BSD
  58  *
  59  * Copyright (c) 2014 Advanced Micro Devices, Inc.
  60  * All rights reserved.
  61  *
  62  * Redistribution and use in source and binary forms, with or without
  63  * modification, are permitted provided that the following conditions are met:
  64  *     * Redistributions of source code must retain the above copyright
  65  *       notice, this list of conditions and the following disclaimer.
  66  *     * Redistributions in binary form must reproduce the above copyright
  67  *       notice, this list of conditions and the following disclaimer in the
  68  *       documentation and/or other materials provided with the distribution.
  69  *     * Neither the name of Advanced Micro Devices, Inc. nor the
  70  *       names of its contributors may be used to endorse or promote products
  71  *       derived from this software without specific prior written permission.
  72  *
  73  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  74  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  75  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  76  * ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
  77  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  78  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  79  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  80  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  81  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  82  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  83  *
  84  * This file incorporates work covered by the following copyright and
  85  * permission notice:
  86  *     The Synopsys DWC ETHER XGMAC Software Driver and documentation
  87  *     (hereinafter "Software") is an unsupported proprietary work of Synopsys,
  88  *     Inc. unless otherwise expressly agreed to in writing between Synopsys
  89  *     and you.
  90  *
  91  *     The Software IS NOT an item of Licensed Software or Licensed Product
  92  *     under any End User Software License Agreement or Agreement for Licensed
  93  *     Product with Synopsys or any supplement thereto.  Permission is hereby
  94  *     granted, free of charge, to any person obtaining a copy of this software
  95  *     annotated with this license and the Software, to deal in the Software
  96  *     without restriction, including without limitation the rights to use,
  97  *     copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  98  *     of the Software, and to permit persons to whom the Software is furnished
  99  *     to do so, subject to the following conditions:
 100  *
 101  *     The above copyright notice and this permission notice shall be included
 102  *     in all copies or substantial portions of the Software.
 103  *
 104  *     THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
 105  *     BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 106  *     TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 107  *     PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
 108  *     BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 109  *     CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 110  *     SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 111  *     INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 112  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 113  *     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 114  *     THE POSSIBILITY OF SUCH DAMAGE.
 115  */
 116
 117 #include "xgbe.h"
 118 #include "xgbe-common.h"
 119
 120 static void xgbe_unmap_rdata(struct xgbe_prv_data *, struct xgbe_ring_data *);
 121
 122 static void xgbe_free_ring(struct xgbe_prv_data *pdata,
 123                            struct xgbe_ring *ring)
 124 {
 125         struct xgbe_ring_data *rdata;
 126         unsigned int i;
 127
 128         if (!ring)
 129                 return;
 130
 131         if (ring->rdata) {
 132                 for (i = 0; i < ring->rdesc_count; i++) {
 133                         rdata = XGBE_GET_DESC_DATA(ring, i);
 134                         xgbe_unmap_rdata(pdata, rdata);
 135                 }
 136
 137                 kfree(ring->rdata);
 138                 ring->rdata = NULL;
 139         }
 140
 141         if (ring->rx_hdr_pa.pages) {
 142                 dma_unmap_page(pdata->dev, ring->rx_hdr_pa.pages_dma,
 143                                ring->rx_hdr_pa.pages_len, DMA_FROM_DEVICE);
 144                 put_page(ring->rx_hdr_pa.pages);
 145
 146                 ring->rx_hdr_pa.pages = NULL;
 147                 ring->rx_hdr_pa.pages_len = 0;
 148                 ring->rx_hdr_pa.pages_offset = 0;
 149                 ring->rx_hdr_pa.pages_dma = 0;
 150         }
 151
 152         if (ring->rx_buf_pa.pages) {
 153                 dma_unmap_page(pdata->dev, ring->rx_buf_pa.pages_dma,
 154                                ring->rx_buf_pa.pages_len, DMA_FROM_DEVICE);
 155                 put_page(ring->rx_buf_pa.pages);
 156
 157                 ring->rx_buf_pa.pages = NULL;
 158                 ring->rx_buf_pa.pages_len = 0;
 159                 ring->rx_buf_pa.pages_offset = 0;
 160                 ring->rx_buf_pa.pages_dma = 0;
 161         }
 162
 163         if (ring->rdesc) {
 164                 dma_free_coherent(pdata->dev,
 165                                   (sizeof(struct xgbe_ring_desc) *
 166                                    ring->rdesc_count),
 167                                   ring->rdesc, ring->rdesc_dma);
 168                 ring->rdesc = NULL;
 169         }
 170 }
 171
 172 static void xgbe_free_ring_resources(struct xgbe_prv_data *pdata)
 173 {
 174         struct xgbe_channel *channel;
 175         unsigned int i;
 176
 177         DBGPR("-->xgbe_free_ring_resources\n");
 178
 179         channel = pdata->channel;
 180         for (i = 0; i < pdata->channel_count; i++, channel++) {
 181                 xgbe_free_ring(pdata, channel->tx_ring);
 182                 xgbe_free_ring(pdata, channel->rx_ring);
 183         }
 184
 185         DBGPR("<--xgbe_free_ring_resources\n");
 186 }
 187
 188 static int xgbe_init_ring(struct xgbe_prv_data *pdata,
 189                           struct xgbe_ring *ring, unsigned int rdesc_count)
 190 {
 191         DBGPR("-->xgbe_init_ring\n");
 192
 193         if (!ring)
 194                 return 0;
 195
 196         /* Descriptors */
 197         ring->rdesc_count = rdesc_count;
 198         ring->rdesc = dma_alloc_coherent(pdata->dev,
 199                                          (sizeof(struct xgbe_ring_desc) *
 200                                           rdesc_count), &ring->rdesc_dma,
 201                                          GFP_KERNEL);
 202         if (!ring->rdesc)
 203                 return -ENOMEM;
 204
 205         /* Descriptor information */
 206         ring->rdata = kcalloc(rdesc_count, sizeof(struct xgbe_ring_data),
 207                               GFP_KERNEL);
 208         if (!ring->rdata)
 209                 return -ENOMEM;
 210
 211         netif_dbg(pdata, drv, pdata->netdev,
 212                   "rdesc=%p, rdesc_dma=%pad, rdata=%p\n",
 213                   ring->rdesc, &ring->rdesc_dma, ring->rdata);
 214
 215         DBGPR("<--xgbe_init_ring\n");
 216
 217         return 0;
 218 }
 219
 220 static int xgbe_alloc_ring_resources(struct xgbe_prv_data *pdata)
 221 {
 222         struct xgbe_channel *channel;
 223         unsigned int i;
 224         int ret;
 225
 226         DBGPR("-->xgbe_alloc_ring_resources\n");
 227
 228         channel = pdata->channel;
 229         for (i = 0; i < pdata->channel_count; i++, channel++) {
 230                 netif_dbg(pdata, drv, pdata->netdev, "%s - Tx ring:\n",
 231                           channel->name);
 232
 233                 ret = xgbe_init_ring(pdata, channel->tx_ring,
 234                                      pdata->tx_desc_count);
 235                 if (ret) {
 236                         netdev_alert(pdata->netdev,
 237                                      "error initializing Tx ring\n");
 238                         goto err_ring;
 239                 }
 240
 241                 netif_dbg(pdata, drv, pdata->netdev, "%s - Rx ring:\n",
 242                           channel->name);
 243
 244                 ret = xgbe_init_ring(pdata, channel->rx_ring,
 245                                      pdata->rx_desc_count);
 246                 if (ret) {
 247                         netdev_alert(pdata->netdev,
 248                                      "error initializing Rx ring\n");
 249                         goto err_ring;
 250                 }
 251         }
 252
 253         DBGPR("<--xgbe_alloc_ring_resources\n");
 254
 255         return 0;
 256
 257 err_ring:
 258         xgbe_free_ring_resources(pdata);
 259
 260         return ret;
 261 }
 262
 263 static int xgbe_alloc_pages(struct xgbe_prv_data *pdata,
 264                             struct xgbe_page_alloc *pa, gfp_t gfp, int order)
 265 {
 266         struct page *pages = NULL;
 267         dma_addr_t pages_dma;
 268         int ret;
 269
 270         /* Try to obtain pages, decreasing order if necessary */
 271         gfp |= __GFP_COLD | __GFP_COMP | __GFP_NOWARN;
 272         while (order >= 0) {
 273                 pages = alloc_pages(gfp, order);
 274                 if (pages)
 275                         break;
 276
 277                 order--;
 278         }
 279         if (!pages)
 280                 return -ENOMEM;
 281
 282         /* Map the pages */
 283         pages_dma = dma_map_page(pdata->dev, pages, 0,
 284                                  PAGE_SIZE << order, DMA_FROM_DEVICE);
 285         ret = dma_mapping_error(pdata->dev, pages_dma);
 286         if (ret) {
 287                 put_page(pages);
 288                 return ret;
 289         }
 290
 291         pa->pages = pages;
 292         pa->pages_len = PAGE_SIZE << order;
 293         pa->pages_offset = 0;
 294         pa->pages_dma = pages_dma;
 295
 296         return 0;
 297 }
 298
 299 static void xgbe_set_buffer_data(struct xgbe_buffer_data *bd,
 300                                  struct xgbe_page_alloc *pa,
 301                                  unsigned int len)
 302 {
 303         get_page(pa->pages);
 304         bd->pa = *pa;
 305
 306         bd->dma_base = pa->pages_dma;
 307         bd->dma_off = pa->pages_offset;
 308         bd->dma_len = len;
 309
 310         pa->pages_offset += len;
 311         if ((pa->pages_offset + len) > pa->pages_len) {
 312                 /* This data descriptor is responsible for unmapping page(s) */
 313                 bd->pa_unmap = *pa;
 314
 315                 /* Get a new allocation next time */
 316                 pa->pages = NULL;
 317                 pa->pages_len = 0;
 318                 pa->pages_offset = 0;
 319                 pa->pages_dma = 0;
 320         }
 321 }
 322
 323 static int xgbe_map_rx_buffer(struct xgbe_prv_data *pdata,
 324                               struct xgbe_ring *ring,
 325                               struct xgbe_ring_data *rdata)
 326 {
 327         int order, ret;
 328
 329         if (!ring->rx_hdr_pa.pages) {
 330                 ret = xgbe_alloc_pages(pdata, &ring->rx_hdr_pa, GFP_ATOMIC, 0);
 331                 if (ret)
 332                         return ret;
 333         }
 334
 335         if (!ring->rx_buf_pa.pages) {
 336                 order = max_t(int, PAGE_ALLOC_COSTLY_ORDER - 1, 0);
 337                 ret = xgbe_alloc_pages(pdata, &ring->rx_buf_pa, GFP_ATOMIC,
 338                                        order);
 339                 if (ret)
 340                         return ret;
 341         }
 342
 343         /* Set up the header page info */
 344         xgbe_set_buffer_data(&rdata->rx.hdr, &ring->rx_hdr_pa,
 345                              XGBE_SKB_ALLOC_SIZE);
 346
 347         /* Set up the buffer page info */
 348         xgbe_set_buffer_data(&rdata->rx.buf, &ring->rx_buf_pa,
 349                              pdata->rx_buf_size);
 350
 351         return 0;
 352 }
 353
 354 static void xgbe_wrapper_tx_descriptor_init(struct xgbe_prv_data *pdata)
 355 {
 356         struct xgbe_hw_if *hw_if = &pdata->hw_if;
 357         struct xgbe_channel *channel;
 358         struct xgbe_ring *ring;
 359         struct xgbe_ring_data *rdata;
 360         struct xgbe_ring_desc *rdesc;
 361         dma_addr_t rdesc_dma;
 362         unsigned int i, j;
 363
 364         DBGPR("-->xgbe_wrapper_tx_descriptor_init\n");
 365
 366         channel = pdata->channel;
 367         for (i = 0; i < pdata->channel_count; i++, channel++) {
 368                 ring = channel->tx_ring;
 369                 if (!ring)
 370                         break;
 371
 372                 rdesc = ring->rdesc;
 373                 rdesc_dma = ring->rdesc_dma;
 374
 375                 for (j = 0; j < ring->rdesc_count; j++) {
 376                         rdata = XGBE_GET_DESC_DATA(ring, j);
 377
 378                         rdata->rdesc = rdesc;
 379                         rdata->rdesc_dma = rdesc_dma;
 380
 381                         rdesc++;
 382                         rdesc_dma += sizeof(struct xgbe_ring_desc);
 383                 }
 384
 385                 ring->cur = 0;
 386                 ring->dirty = 0;
 387                 memset(&ring->tx, 0, sizeof(ring->tx));
 388
 389                 hw_if->tx_desc_init(channel);
 390         }
 391
 392         DBGPR("<--xgbe_wrapper_tx_descriptor_init\n");
 393 }
 394
 395 static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
 396 {
 397         struct xgbe_hw_if *hw_if = &pdata->hw_if;
 398         struct xgbe_channel *channel;
 399         struct xgbe_ring *ring;
 400         struct xgbe_ring_desc *rdesc;
 401         struct xgbe_ring_data *rdata;
 402         dma_addr_t rdesc_dma;
 403         unsigned int i, j;
 404
 405         DBGPR("-->xgbe_wrapper_rx_descriptor_init\n");
 406
 407         channel = pdata->channel;
 408         for (i = 0; i < pdata->channel_count; i++, channel++) {
 409                 ring = channel->rx_ring;
 410                 if (!ring)
 411                         break;
 412
 413                 rdesc = ring->rdesc;
 414                 rdesc_dma = ring->rdesc_dma;
 415
 416                 for (j = 0; j < ring->rdesc_count; j++) {
 417                         rdata = XGBE_GET_DESC_DATA(ring, j);
 418
 419                         rdata->rdesc = rdesc;
 420                         rdata->rdesc_dma = rdesc_dma;
 421
 422                         if (xgbe_map_rx_buffer(pdata, ring, rdata))
 423                                 break;
 424
 425                         rdesc++;
 426                         rdesc_dma += sizeof(struct xgbe_ring_desc);
 427                 }
 428
 429                 ring->cur = 0;
 430                 ring->dirty = 0;
 431
 432                 hw_if->rx_desc_init(channel);
 433         }
 434
 435         DBGPR("<--xgbe_wrapper_rx_descriptor_init\n");
 436 }
 437
 438 static void xgbe_unmap_rdata(struct xgbe_prv_data *pdata,
 439                              struct xgbe_ring_data *rdata)
 440 {
 441         if (rdata->skb_dma) {
 442                 if (rdata->mapped_as_page) {
 443                         dma_unmap_page(pdata->dev, rdata->skb_dma,
 444                                        rdata->skb_dma_len, DMA_TO_DEVICE);
 445                 } else {
 446                         dma_unmap_single(pdata->dev, rdata->skb_dma,
 447                                          rdata->skb_dma_len, DMA_TO_DEVICE);
 448                 }
 449                 rdata->skb_dma = 0;
 450                 rdata->skb_dma_len = 0;
 451         }
 452
 453         if (rdata->skb) {
 454                 dev_kfree_skb_any(rdata->skb);
 455                 rdata->skb = NULL;
 456         }
 457
 458         if (rdata->rx.hdr.pa.pages)
 459                 put_page(rdata->rx.hdr.pa.pages);
 460
 461         if (rdata->rx.hdr.pa_unmap.pages) {
 462                 dma_unmap_page(pdata->dev, rdata->rx.hdr.pa_unmap.pages_dma,
 463                                rdata->rx.hdr.pa_unmap.pages_len,
 464                                DMA_FROM_DEVICE);
 465                 put_page(rdata->rx.hdr.pa_unmap.pages);
 466         }
 467
 468         if (rdata->rx.buf.pa.pages)
 469                 put_page(rdata->rx.buf.pa.pages);
 470
 471         if (rdata->rx.buf.pa_unmap.pages) {
 472                 dma_unmap_page(pdata->dev, rdata->rx.buf.pa_unmap.pages_dma,
 473                                rdata->rx.buf.pa_unmap.pages_len,
 474                                DMA_FROM_DEVICE);
 475                 put_page(rdata->rx.buf.pa_unmap.pages);
 476         }
 477
 478         memset(&rdata->tx, 0, sizeof(rdata->tx));
 479         memset(&rdata->rx, 0, sizeof(rdata->rx));
 480
 481         rdata->mapped_as_page = 0;
 482
 483         if (rdata->state_saved) {
 484                 rdata->state_saved = 0;
 485                 rdata->state.skb = NULL;
 486                 rdata->state.len = 0;
 487                 rdata->state.error = 0;
 488         }
 489 }
 490
 491 static int xgbe_map_tx_skb(struct xgbe_channel *channel, struct sk_buff *skb)
 492 {
 493         struct xgbe_prv_data *pdata = channel->pdata;
 494         struct xgbe_ring *ring = channel->tx_ring;
 495         struct xgbe_ring_data *rdata;
 496         struct xgbe_packet_data *packet;
 497         struct skb_frag_struct *frag;
 498         dma_addr_t skb_dma;
 499         unsigned int start_index, cur_index;
 500         unsigned int offset, tso, vlan, datalen, len;
 501         unsigned int i;
 502
 503         DBGPR("-->xgbe_map_tx_skb: cur = %d\n", ring->cur);
 504
 505         offset = 0;
 506         start_index = ring->cur;
 507         cur_index = ring->cur;
 508
 509         packet = &ring->packet_data;
 510         packet->rdesc_count = 0;
 511         packet->length = 0;
 512
 513         tso = XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES,
 514                              TSO_ENABLE);
 515         vlan = XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES,
 516                               VLAN_CTAG);
 517
 518         /* Save space for a context descriptor if needed */
 519         if ((tso && (packet->mss != ring->tx.cur_mss)) ||
 520             (vlan && (packet->vlan_ctag != ring->tx.cur_vlan_ctag)))
 521                 cur_index++;
 522         rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 523
 524         if (tso) {
 525                 /* Map the TSO header */
 526                 skb_dma = dma_map_single(pdata->dev, skb->data,
 527                                          packet->header_len, DMA_TO_DEVICE);
 528                 if (dma_mapping_error(pdata->dev, skb_dma)) {
 529                         netdev_alert(pdata->netdev, "dma_map_single failed\n");
 530                         goto err_out;
 531                 }
 532                 rdata->skb_dma = skb_dma;
 533                 rdata->skb_dma_len = packet->header_len;
 534                 netif_dbg(pdata, tx_queued, pdata->netdev,
 535                           "skb header: index=%u, dma=%pad, len=%u\n",
 536                           cur_index, &skb_dma, packet->header_len);
 537
 538                 offset = packet->header_len;
 539
 540                 packet->length += packet->header_len;
 541
 542                 cur_index++;
 543                 rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 544         }
 545
 546         /* Map the (remainder of the) packet */
 547         for (datalen = skb_headlen(skb) - offset; datalen; ) {
 548                 len = min_t(unsigned int, datalen, XGBE_TX_MAX_BUF_SIZE);
 549
 550                 skb_dma = dma_map_single(pdata->dev, skb->data + offset, len,
 551                                          DMA_TO_DEVICE);
 552                 if (dma_mapping_error(pdata->dev, skb_dma)) {
 553                         netdev_alert(pdata->netdev, "dma_map_single failed\n");
 554                         goto err_out;
 555                 }
 556                 rdata->skb_dma = skb_dma;
 557                 rdata->skb_dma_len = len;
 558                 netif_dbg(pdata, tx_queued, pdata->netdev,
 559                           "skb data: index=%u, dma=%pad, len=%u\n",
 560                           cur_index, &skb_dma, len);
 561
 562                 datalen -= len;
 563                 offset += len;
 564
 565                 packet->length += len;
 566
 567                 cur_index++;
 568                 rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 569         }
 570
 571         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 572                 netif_dbg(pdata, tx_queued, pdata->netdev,
 573                           "mapping frag %u\n", i);
 574
 575                 frag = &skb_shinfo(skb)->frags[i];
 576                 offset = 0;
 577
 578                 for (datalen = skb_frag_size(frag); datalen; ) {
 579                         len = min_t(unsigned int, datalen,
 580                                     XGBE_TX_MAX_BUF_SIZE);
 581
 582                         skb_dma = skb_frag_dma_map(pdata->dev, frag, offset,
 583                                                    len, DMA_TO_DEVICE);
 584                         if (dma_mapping_error(pdata->dev, skb_dma)) {
 585                                 netdev_alert(pdata->netdev,
 586                                              "skb_frag_dma_map failed\n");
 587                                 goto err_out;
 588                         }
 589                         rdata->skb_dma = skb_dma;
 590                         rdata->skb_dma_len = len;
 591                         rdata->mapped_as_page = 1;
 592                         netif_dbg(pdata, tx_queued, pdata->netdev,
 593                                   "skb frag: index=%u, dma=%pad, len=%u\n",
 594                                   cur_index, &skb_dma, len);
 595
 596                         datalen -= len;
 597                         offset += len;
 598
 599                         packet->length += len;
 600
 601                         cur_index++;
 602                         rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 603                 }
 604         }
 605
 606         /* Save the skb address in the last entry. We always have some data
 607          * that has been mapped so rdata is always advanced past the last
 608          * piece of mapped data - use the entry pointed to by cur_index - 1.
 609          */
 610         rdata = XGBE_GET_DESC_DATA(ring, cur_index - 1);
 611         rdata->skb = skb;
 612
 613         /* Save the number of descriptor entries used */
 614         packet->rdesc_count = cur_index - start_index;
 615
 616         DBGPR("<--xgbe_map_tx_skb: count=%u\n", packet->rdesc_count);
 617
 618         return packet->rdesc_count;
 619
 620 err_out:
 621         while (start_index < cur_index) {
 622                 rdata = XGBE_GET_DESC_DATA(ring, start_index++);
 623                 xgbe_unmap_rdata(pdata, rdata);
 624         }
 625
 626         DBGPR("<--xgbe_map_tx_skb: count=0\n");
 627
 628         return 0;
 629 }
 630
 631 void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
 632 {
 633         DBGPR("-->xgbe_init_function_ptrs_desc\n");
 634
 635         desc_if->alloc_ring_resources = xgbe_alloc_ring_resources;
 636         desc_if->free_ring_resources = xgbe_free_ring_resources;
 637         desc_if->map_tx_skb = xgbe_map_tx_skb;
 638         desc_if->map_rx_buffer = xgbe_map_rx_buffer;
 639         desc_if->unmap_rdata = xgbe_unmap_rdata;
 640         desc_if->wrapper_tx_desc_init = xgbe_wrapper_tx_descriptor_init;
 641         desc_if->wrapper_rx_desc_init = xgbe_wrapper_rx_descriptor_init;
 642
 643         DBGPR("<--xgbe_init_function_ptrs_desc\n");
 644 }